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# System prepended metadata

title: 55 Security
tags: [dartmouth]

---

# 55 Security
###### tags: `dartmouth`

1. **Fundamentals** (Ch. 1)
    - Confidentiality, Integrity, and Availability
        - **Confidentiality**: the ability of a system to ensure that an asset is *viewed* only by authorized parties
        - **Integrity**: the ability of a system to ensure that an asset is *modified* only by authorized parties
        - **Availability**: the ability of a system to ensure that an asset *can be used* by any authorized parties
    - Identification and Authentication
        - **Identification**: the act of asserting who a person is
        - **Authentication**: the act of proving that asserted identity: that the person is who she says she is

2. **Authorization and Access Control** (Ch. 2.0-2.2)
	- Saltzer’s and Schroeder’s principles of secure design
	    - **Economy of mechanism**: Keep the design as simple and small as possible
        - **Fail-safe defaults**: Base access decisions on permission rather than exclusion
        - **Complete mediation**: Every access to every object must be checked for authority
        - **Open design**: The design should not be secret
        - **Separation of privilege**: Where feasible, a protection mechanism that requires two keys to unlock it is more robust and flexible than one that allows access to the presenter of only a single key
        - **Least privilege**: Every program and every user of the system should operate using the least set of privileges necessary to complete the job
        - **Least common mechanism**: Minimize the amount of mechanism common to more than one user and depended on by all users
        - **Psychological acceptability**: It is essential that the human interface be designed for ease of use, so that users routinely and automatically apply the protection mechanisms correctly
        - **Work factor**: Compare the cost of circumventing the mechanism with the resources of a potential attacker
        - **Compromise recording**: It is sometimes suggested that mechanisms that reliably record that a compromise of information has occurred can be used in place of more elaborate mechanisms that completely prevent loss
    - Access control
        - **Access control**: limiting who can access what in what ways
        - **Effective Policy Implementation**:
            - Check every access
            - Enforce least privilege
            - Verify acceptable usage
3. **Ciphers and cryptographic hashes** (Ch. 2.3 and appendix)
	- Symmetric and asymmetric ciphers and their uses
	    - Symmetric cipher: DES, Triple-DES, AES
	    - Asymmetric cipher: RSA
	- Cryptographic hash functions
	    - Easy to compute HASH(x)
	    - Hard to provide x given HASH(x)
	    - Infeasible to calculate two messages x and y such that HASH(x) = HASH(y)
	    - Small change in input x results in a large change in the output HASH(x)
	- Digital signatures
	- Certificates and public key infrastructure
	    - PKI Hierarchy
	    - Cross certification
	    - Bridge CA
4. **Malware** (Ch. 5)
	- Viruses and worms in general
		- **Virus**: code with malicious purpose; intended to spread
		- **Worm**: program that spreads copies of itself through a network
		- **Trojan horse**: program with benign apparent effect but second, hidden, malicious effect
5. **Networks** (Ch. 6, but not wireless)
	- Network threats
	    - **interception**, or unauthorized viewing
	    - **modification**, or unauthorized change
	    - **fabrication**, or unauthorized creation
	    - **interruption**, or preventing authorized access
	- Denial of service and distributed denial of service protections (**DoS/DDoS**)
	    - DoS attacks usually try to flood a victim with excessive demand.
	    - DDoS attacks change the balance between adversary and victim by marshalling many forces on the attack side.
	        - bot and botnet
	- SSL (Secure Sockets Layer) and VPN
	    - **SSL**: encrypted communication between a browser and the remote web host (its websites)
	    - **VPN**: encrypted links within a network
	        - simulates the security of a dedicated, protected communication line on a shared network.
	- Firewalls
	    - **Firewall**: a computer traffic cop that permits or blocks data flow between two parts of a network architecture. It is the only link between parts.
	    - Firewalls enforce predetermined rules governing what traffic can flow.
	    - ![](https://i.imgur.com/f0cj7pu.png)

	- Intrusion detection and prevention systems (IDS) (Ch. 6.8)
	    - **IDS**: a device, typically another separate computer, that monitors activity to identify malicious or suspicious events.
	    - **Intrusion prevention systems**: extend IDS technology with built-in protective response.
6. **Cloud** (Ch. 8)
	- What is a cloud service?
	    - On-demand self-service.
        - Broad network access.
        - Resource pooling.
        - Rapid elasticity.
        - Measured service.
	- Risks to consider when choosing cloud services
	    - Identify assets
	    - Determine vulnerabilities
	    - Estimate likelihood of exploitation
	    - Compute expected loss
	    - Survey and select new controls
	    - Project savings
	- Security tools for cloud environments (Ch. 8.3)
	    - Data Protection in the Cloud
	    - Cloud Storage
	    - Data Loss Prevention (DLP)
	    - Cloud Application Security
	    - Logging and Incident Response
7. **Security management**(Ch. 10)
	- Security & Incident response
	    - **Incident Response Plans**: tells whom to contact in the event of an incident, which may be just an unconfirmed, unusual situation
	        - define what constitutes an *incident*
	        - identify who is responsible for *taking charge* of the situation
	        - describe the plan of *action*
	    - Advance Planning
	    - Responding: Incident Response Teams
	    - “*Is this really an incident?*” is the most important question.
	    - After the Incident Is Resolved:
	        - *Is any security control action to be taken?*
	        - *Did the incident response plan work?*
	- Business continuity planning (Ch. 10.2)
	    - **Business continuity planning**: guides response to a crisis that threatens a business’s existence.
	        - focuses on business needs
	    - Assess the business impact of a crisis.
	    - Develop a strategy to control impact.
	    - Develop and implement a plan for the strategy
	        - who in charge? what to do? who does it?
	- Handling natural and human-caused disasters
8. **Privacy** (Ch. 9)
	- Privacy: what is it?
	    - **Privacy**: the right to control who knows certain things about you.
	    - sensitive data (object)
	    - affected parties (subject)
	    - controlled disclosure (access right)
	- **Privacy** as an aspect of **security**
        ![](https://i.imgur.com/cj7t11H.png)
	- **Authentication** effects on privacy (Ch. 9.3)
	    - Authentication is confirming an asserted identity. Inferring an identity from authentication data is far harder and less certain.
	    - ![](https://i.imgur.com/7xFYhl8.png)
	- Privacy and the Internet (Ch. 9.5)
	- Privacy enhancing technology (e.g., Zero Knowledge)
9. **Legal and ethics** (Ch. 11.0-11.6)
	- Value of information
	    - Information has value unrelated to whatever medium contains it
	    - Information Can Be Replicated
	    - Information Has a Minimal Marginal Cost
	    - The Value of Information Is Often Time Dependent
	    - Information Is Often Transferred Intangibly
	- legal and ethical issues/challenges
	    - Computer crime is a multinational activity.
	    - Computer attacks affecting many people tend to be complex, involving people and facilities in several countries, thus complicating prosecution.
	    - Even with the definitions included in the statutes, the courts must interpret what a computer is.
10. **IoT** (Ch. 13.1)
    - **IoT**: A world of interconnected smart devices not ordinarily thought of as computers.
	- Security and privacy issues of the IoT
11. **Voting** (Ch. 13.3)
	- Goals of elections
	- Constraints on elections
	- Pros and Cons of election/ballot technology options
12. **Cyberwar** (Ch. 13.4)
	- What is cyberwar?
	- Attribution
	- Asymmetry
	- Defense and deterrence
13. **AI Risks** (notes and slides)
